Re: [pve-devel] [PATCH qemu-server] migration: prohibit renaming cloud-init drive

[Fiona Ebner <f.ebner@proxmox.com>]

Am 10.03.26 um 1:30 PM schrieb Fiona Ebner:
> Am 10.03.26 um 1:22 PM schrieb Daniel Kral:
>> On Mon Dec 1, 2025 at 2:51 PM CET, Fiona Ebner wrote:
>>> Usually, disks are allowed to be renamed during migration if there is
>>> a naming conflict caused by a left-over disk on the target. However,
>>> the type of the cloud-init disk is encoded in its name, so it must not
>>> be renamed or it cannot be recognized as a cloud-init disk anymore, as
>>> reported in the community forum [0].
>>>
>>> [0]: https://forum.proxmox.com/threads/167767/
>>
>> A user in the community forum [1] reported that if a VM is moved to
>> another node during a fence recovery, the VM will fail to migrate back,
>> e.g., if a node affinity rule prioritizes the previous node.
>>
>> This patch is correct to not allow renaming cloudinit images, but I
>> wonder if it would be a reasonable idea to allow overriding existing
>> cloudinit images on the target node as these are auto-generated?
>>
>> That would probably need a `--allow-override` flag for pvesm, which
>> would require that the target host can understand the parameter though.
>>
>> [1] https://forum.proxmox.com/threads/181516/
> 
> I think we could remove left-over cloud-init images as part of the
> 'pvesr prepare-local-job' on the target?

Ah wait, it doesn't only affect the scenario with replication. The
'pvesm apiinfo' command was added when introducing the '--allow-rename'
flag. You could add '--allow-override', bump the API and then use that
call to check if it is understood by the target.

Or maybe we can add some kind of preparatory tunnel command for removing
any left-over cloud-init images?